This invention relates generally to refrigerator cabinets, and more particularly to a mounting bracket for attaching a hinge plate and a support member such as a leveling leg or roller directly on the sheet metal cabinet.
A refrigerator cabinet requires a certain amount stiffness and rigidity, not only because the refrigerator itself may weigh several hundred pounds but also because the contents may also be fairly heavy, the refrigerator is subject to continued stress from the opening and closing of the doors, and the refrigerator itself must be movable across the floor for cleaning purposes. In order to achieve proper operation of the door, the hinge assembly must be precisely mounted to allow proper sealing of the gasket around the door, while the cabinet must be leveled on the floor for proper door opening and closing. The latter requires the presence of either screw-adjustable leveling legs or adjustable rollers as options available to the user.
The problem has been complicated by changes in refrigerator design. The use of foamed-in-place insulation, while adding greatly to the rigidity of the cabinet, has allowed the use of much thinner sheet metal. While the use of thinner metal has also reduced the cabinet weight, the construction requires that in some locations, the metal must be reinforced to provide the necessary stiffness and rigidity for the cabinet.
This matter has been further complicated by the increasing use of pre-finished and pre-painted sheet metal, particularly for the exterior panels of the cabinet, since the use of such sheet metal means that welding and similar methods cannot be used but that the fastening together of the various parts must therefore rely entirely upon mechanical connections.
In cabinets of this type, the bottom portion of the cabinet which covers the insulation must be spaced a certain distance above the floor to allow air circulation beneath the cabinet. Therefore, in many constructions of refrigerator cabinets, particularly using pre-painted sheet metals, it has been necessary to use a base sub-frame which fits beneath the insulation bottom panel and which also generally provides a support for the compressor and other portions of the mechanism which are generally located in a housing at the bottom rear of the cabinet and exposed to air for cooling purposes. Because a sub-frame is used, it is necessary to provide a decorative finish over the frame, either in the form of separate panels or by extending the outer sides of the cabinet surface downward over the exterior of the frame. Thus, a rather substantial and heavy sub-frame can be used within the refrigerator cabinet to provide the necessary rigidity, although the resulting construction generally has a rather high cost of manufacture.
An alternative construction which eliminates a heavy sub-frame is shown in the U.S. patent of Earl Anderson No. 3,948,410, granted Apr. 6, 1976, assigned to the assignee of the present invention and incorporated herein by reference. With this construction, the sheet metal for the outer surface of the cabinet uses a single piece to form both side walls, the top and the bottom wall, and is joined at a seam along the one bottom edge. To support the cabinet, a separate base is formed from a single piece of pre-finished material formed into a rectangle having side walls and inwardly extending flanges at the top and bottom edges. The top flanges are fastened directly to the bottom surface of the shell by mechanical fastening means, while the bottom flanges serve as a mount for leveling legs or the like to support the refrigerator cabinet and allow for the necessary leveling.
With the cabinet construction of the type described above, the base member is generally used also to support the lower hinge bracket for the door, and since doors are generally reversible to be hinged on either side, it is necessary to provide a mount for a hinge plate at each front corner of the base. To allow sufficient grip for the fastening screws, it is also necessary to provide a tapping plate on the rear or inner face of the base. Furthermore, screw-type leveling legs are generally mounted in a threaded bushing mounted on the interned lower flange, and since the thickness of the metal used for the base is generally relatively thin for easy fabrication, it is possible that continued movement of the refrigerator will cause the base to flex and cause possible misalignment of the hinge bracket or the leveling legs, therefore requiring further adjustment of these members on the refrigerator.
A popular option on refrigerators these days is to provide rollers to allow the refrigerator to be easily moved away from the wall for easy cleaning of the floor surface and rear portion of the refrigerator. For rollers to be effective in eliminating any sliding friction, it is necessary to have rollers at both the front and back corners. However, it is generally desirable to be able to disable the front rollers by retracting them and rely on a leveling leg for support when the refrigerator is in the operating position to prevent undesired movement of the refrigerator along the floor. Thus, when the roller arrangement is used, it is necessary to provide both screw-type leveling legs at each of the front corners as well as a roller assembly that can be raised or lowered with respect to the refrigerator cabinet to move it to and from an operating position.
One such arrangement is shown in the U.S. patent of Douglas E. Weaver No. 4,783,879, granted Nov. 15, 1988, assigned to the assignee of the present invention and incorporated herein by reference. In the arrangement shown in this patent, the refrigerator generally uses an elongated base rail along each side, and while the base rail can support rollers at the back, it has generally been necessary to mount adjustable rollers on a separate frame attached to the underside of the insulation bottom. With this arrangement, it is possible that if the refrigerator suffers high enough impact loads, such as being dropped so that the rollers must absorb the impact, the mounting may become distorted and the rollers less effective in operation.